CHEM 1001 Chapter Notes - Chapter ch.1: Molar Mass, Chemical Compound, Chemical Formula

• School: Carleton University
• Department: Chemistry
• Course: CHEM 1001
• Professor: Bob Burk

Document Summary

Molecules: combination of atoms to make a substance. Chemical compound: is a substance containing more than one element. Physical properties: can be measured without observing a chemical reaction (size, colour and mass) Mass: quantity of matterfor chemical transformations to occur. Temperature: determines the direction of heat flow. ( energy found in the chemical system) Chemical properties: displayed only during a chemical transformation. Numerical results for scientific values: magnitude, unit(indicator of scale) and precision. Magnitude, to summarize values we use scientific notation: 3x 10-10m. 1l =10-3 m3, 1ml = 10-3l = 1cm3. 1 bar= 750. 06 torr which can give two ratios 1= 1bar/750. 06 tor and 1= 750. 06 torr/1bar. Ex: want to convert 2 bar into torr. Conversion of temperature : t(k) = t(c) + 273. 15o , t(c)= t(k) 273. 15o. Accuracy: describes how close a measurement is to its true value. Significant figures: the number of digits expressed in a numerical value. Ex: 505 = 3 significant number 5. 00x 103 = 3.